Epilepsy during pregnancy can pose some unique concerns. However, most women who have epilepsy deliver healthy babies. If you have epilepsy and are considering pregnancy, here's what you need to know.

Some drugs used to treat seizures might contribute to infertility. However, certain anti-seizure medications can also reduce the effectiveness of hormonal birth control methods.

Seizures during pregnancy can cause:

Fetal heart rate deceleration

Fetal injury, premature separation of the placenta from the uterus (placental abruption) or miscarriage due to trauma experienced during a seizure

Preterm labor

Premature birth

Every woman reacts to pregnancy differently. For most pregnant women who have epilepsy, seizures remain the same. For a few, seizures become less frequent. For others, particularly women who are sleep deprived or don't take medication as prescribed, pregnancy increases the number of seizures.

Any medication you take during pregnancy can affect your baby. Birth defects — including cleft palate, neural tube defects, skeletal abnormalities, and congenital heart and urinary tract defects — are the primary concern with anti-seizure medications.

For babies whose mothers take anti-seizure medication, the risk of major birth defects is 4 to 6 percent — compared with 2 to 3 percent for all babies. The risk seems to be highest when more than one anti-seizure medication is taken and when a form of the anti-seizure medication valproate (Depacon, Depakote, Depakote ER, others) is used.

A few women can safely taper off their medication before pregnancy. For most women, however, it's best to continue treatment during pregnancy. To minimize the risks for you and your baby, your health care provider will prescribe the safest medication and dosage that's effective for your type of seizures.

Beyond the effects of medications, babies born to mothers who have epilepsy also have a slightly higher risk of developing seizures as they get older.

Before you try to conceive, schedule an appointment with the health care provider who'll be handling your pregnancy. Also meet with other members of your health care team, such as your family doctor or neurologist. They'll evaluate how well you're managing your epilepsy and consider any treatment changes you might need to make before pregnancy begins.

Take your anti-seizure medication exactly as prescribed. Don't adjust the dose or stop taking the medication on your own. Remember, uncontrolled seizures likely pose a greater risk to your baby than does any medication.

During pregnancy, you'll see your health care provider often. Your weight and blood pressure will be checked at every visit, and you might need frequent blood tests to monitor your medication levels. If you're taking anti-seizure medications, your health care provider might recommend oral vitamin K supplements during the last month of pregnancy to help prevent bleeding problems in the baby after birth.

Seizures can be dangerous, but many mothers who have seizures during pregnancy deliver healthy babies. Report the seizure promptly to your health care provider. He or she might adjust your medication to help prevent other seizures. If you have a seizure in the last few months of your pregnancy, your health care provider might monitor your baby at the hospital or clinic.

Your health care provider will closely monitor your baby's health throughout the pregnancy. Frequent ultrasounds might be used to track your baby's growth and development. Your health care provider might recommend other prenatal tests, depending on the circumstances. What you find out might help you understand the odds and make important decisions about your pregnancy.

Most pregnant women who have epilepsy deliver their babies without complications. Women who have epilepsy might use the same methods of pain relief during labor and delivery as other pregnant women.

Seizures don't commonly occur during labor. If you do have a seizure during labor, it might be stopped with intravenous medication. If the seizure is prolonged, your health care provider might deliver the baby by C-section. If you have frequent seizures during your third trimester, your health care provider might recommend an elective C-section to avoid the risk of a seizure during labor.

If your anti-seizure medication dosage is altered for pregnancy, talk to your health care provider about returning to your pre-pregnancy levels shortly after delivery to continue keeping your seizures under control and your medication at safe levels.

Breast-feeding is encouraged for most women who have epilepsy, even those who take anti-seizure medication. Discuss any adjustments you'll need to make with your health care provider ahead of time. Sometimes a change in medication is recommended.

Harden CL, et al. Management issues for women with epilepsy — Focus on pregnancy (an evidence-based review): II. Teratogenesis and perinatal outcomes: Report of the Quality Standards Subcommittee and Therapeutics and Technology Subcommittee of the American Academy of Neurology and the American Epilepsy Society. Epilepsia. 2009;50:1237.

Harden CL, et al. Management issues for women with epilepsy — Focus on pregnancy (an evidence-based review): I. Obstetrical complications and change in seizure frequency: Report of the Quality Standards Subcommittee and Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology and the American Epilepsy Society. Epilepsia. 2009;50:1229.

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